Method of securing covering material to elastic strands for elastic fabrics



S. C. LILLEY March 29, 1938.

METHOD OF SECURING COVERING MATERIAL TO ELASTIC STRANDS FOR ELASTIC FABRICS Filed Oct. 20. 1936 jy /fl Patented Mar. 29, 1938 PATENT OFFICE METHOD OF SECURING COVERING MATE- RIAL TO ELASTIC STRANDS FOR ELASTIC FABRICS Samuel C. Lilley, Hamden, Conn., assignor to The American Mills Company, New Haven, Conn., a corporation of Connecticut Application October 20, 1936, Serial No. 106,579

3 Claims.

This invention relates to an improvement in methods of making covered elastic strands and particularly to methods for securing or anchoring covering material to elastic core-strands, for incorporation into woven, knitted, netted, or the like elastic fabrics.

Heretofore-methods of securing textile covering-strands to elastic core-strands have been proposed, all of which, however, have been open 0 to one or more objections, such as difficulty of manufacture, high cost of manufacture, unsightliness of the product, interference with weaving or other fabricating operations, etc.

One of the objects of the present invention is to provide a superior method for the manufacture of covered elastic strands of the character referred to in which the covering material is efiectively cemented to the elastic core-strand to guard against the creeping of the latter with respect to the former.

A further object is to provide a simple and economical method of securing covering material to elastic core-strands to guard against relative creeping.

Another object is to provide a superior method whereby covering material may be secured to elastic core-strands without materially impairing the efliciency or appearance of the covering material.

A still further object is to provide a superior method for producing elastic strands (comprising an elastic core and a covering cemented thereto) which may be readily incorporated into fabric without interfering with the operation of looms or other fabric-producing machinery.

With the above and other objects in view, as will appear to those skilled in the art from the present disclosure, this invention includes all features in the said disclosure which are novel over the prior art and which are not claimed by me in a separate application.

As will be apparent from the following, the present invention contemplates securing the cov ering material to an elastic core-strand by sub- ,iecting previously-applied potential adhesiveforming material to the action of a suitable solvent while the said covering material is in situ.

In the accompanying drawing:

Fig. 1 is a perspective view of a bare elastic core-strand preparatory to being provided with a cemented-on covering material;

Fig. 2 is a view in side elevation of the elastic core-strand shown as slightly stretched and showing adhesive-forming strands and covering strands applied thereto preparatory to softening the said adhesive-forming strands to adhere the covering-strands in place to the elastic corestrand;

Fig. 3 is a transverse sectional view taken on the line 3-3 of Fig. 2;

Fig. 4 is a longitudinal sectional view taken on the line 4-4 of Fig. 2;

Fig. 5 is a broken view substantially corresponding to Fig. 4 but on a larger scale and showing the covered strand after the adhesive-forming strands have been softened and largely dispersed to adhere the covering-strands to the elastic core-strand, which latter is substantially relaxed;

Fig. 6 is a broken view in side elevation illustrating another mode of applying adhesiveiorming strands and covering-strands to an elastic core-strand;

Fig. 7 is a similar view of still another mode of applying adhesive-forming strands and coveringstrands to an elastic core-strand; and

Fig. 8 is a broken view in side elevation illustrating another mode of adhering covering material to an elastic core-strand.

In carrying out the present invention as illustrated in Figs. 1 to 5 inclusive, a core-strand I0 is employed, which may be of rectangular, round or other cross-sectional form and of such crosssectional dimensions as will enable it to be incorporated into elastic fabrics after it has been covered in a manner as will hereinafter appear.

The core-strands of the present invention may be formed of a variety of elastic materials such, for instance, as the vulcanized rubber compounds common in the industry. The following compound may be mentioned as suited for the production of elastic core-strands when cured for about 45 minutes at approximately-260 F.:

Parts by weight Rubber 100 Sulphur /3 Stearic acid l Symmetrical di-beta-naphthyl-para-phenylenediame 1 Zinc sulphide 5 Phenylhydrazine zinc salt of mercaptobenzothiazole} 1 core-strand in also has helically wrapped around it one or more strands l2 formed of suitable material (specific examples of which are hereinafter recited) which will become tacky or adhesive under the action of a suitable softening material, which latter will, for convenience of description, be referred to as solvent" material or fluid, examples of which will also be hereinafter given. The strands II, also for the purpose of convenience of description, may be properly designated as adhesive-forming" material or strands, inasmuch as they may be viewed as potential adhesives and do not become fully effective until treated with the so-called solvent material, as will more fully hereinafter appear.

The convolutions of the solvent-softenable adhesive-forming strands l2 are, as shown in Fig. 2, interspersed between the convolutions of the covering-strands I I before referred to, both of which types of strands may be concurrently applied to the elastic core-strand III or they may be separately applied thereto if desired.

After both the covering-strands II and the adhesive-forming strands I! are in place upon the elastic core-strand ill, the partly-finished strand may be immersed in or otherwise subjected to the action of a suitable solvent, which will render the said adhesive-forming strands or their equivalent sumciently soft or tacky to adhere the coveringstrands or their equivalent to the elastic corestrand. The adhesive-forming strands, such as l2, may be caused to substantially lose their identity as strands by using a sufliciently-strong solvent over a short period of time or a relativelyweaker solvent over a longer period of time, and be caused to penetrate portions of the covering material such as I l, as is indicated in Fig. 5.

The material from which the adhesive-forming material or strands may be formed in accordance with the present invention, as well as the solvents therefor, may vary widely, and the following is given by way of illustration:

SoIvent-soitenable adhesivetone and alcohol, ether and alcool, etc.

If it is desired to limit the softening or solvent action of the so-called solvent, the said solvent may be diluted, if desired, to such a degree that the adhesive-forming strands will not entirely lose their identity, but will still serve their purpose of adhering the covering-strands to the elastic core-strand.

Furthermore, if it is desired to render the cementing resulting from the softening of the adhesive-forming material more plastic, such material may be treated prior to softening with a suitable plasticizer such, for instance, as diethylphthalate.

The adhesive-forming material chosen should be (as are those before listed) insoluble in water after having been treated with a solvent, in order to permit the fabrics in which the covered elastic strands of the present invention are incorporated, to be laundered.

As before indicated, the elastic core-strands, covering material, the adhesive-forming material, and the solvents may vary widely, and in selecting them forcombination, care should be 1 to an elastic core-strand ll, after which one or more covering-strands I5 may be helically wrapped over the strands II and thecore-strand H in a direction reverse to the inclination of the said strands II.

The partly-completed covered-strand structure of Fig. 6 may be subjected to the action of a suitable solvent which will penetrate the covering material I! and effect the softening of the strands ll so as to cause the same to adhere the covering-strands II and the elastic core-strand together.

If desired and as shown in Fig. '7, a suitable number of solvent-softenable adhesive-forming strands It may be extended longitudinally of an elastic core-strand H. In the covered-strand structure now being described, the strands it are interposed between a group of inner coveringstrands l8 helically applied directly to the elastic core l1 and an outer series of covering-strands I9 helically applied in a direction opposite to the inclination of the inner covering-strands ll.

When the covered-strand structure of Fig. 7 is subjected to the action of a suitable solvent the adhesive-forming strands It may be caused to become so fluid as to penetrate the inner covering II and bond the same to the elastic corestrand ll. By this procedure, the outer coveringstrands I! may also be adhered to the inner covering-strands ll before referred to.

Instead of applying the adhesive material in the form of a strand, a core-strand 20 may be provided with an all-over coating II of a solventsoftenable adhesive-forming material as illustrated in Fig. 8. When the coating 2| is sumciently dry and free of tackiness, coveringstrands 22 may be applied in one or more layers. Upon subjecting the partly-completed coveredstrand structure of Fig. 8 to the action of a suitable solvent, the coating 2| will become suillciently softened to adhere the covering-strands 22 to the elastic core 20.

It will usually be found that after the partlycompleted covered elastic strands of the present invention have been treated with a suitable solvent, preferably when substantially relaxed and either before or after their incorporation into a fabric, that some adhesion will exist between the abutting wrapped or braided coveringstrands. The initial stretching of the completed and dried strand, however, will in most cases break the bond between the various convolutions of the covering material without, however, breaking the bond between the covering material and or other apparatus employed for incorporating the strands of the present invention into a fabric.

The invention may be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

I claim:

in A method of securing covering material to elastic strands for incorporation into elastic fabrics comprising: first stretching an. elastic core-strand; then applying an adhesive-forming material and a covering material in strand form to the elastic core-strand while the same is stretched; and then subjecting the covered strand thus produced to the action of a solvent to effect the softening of the said adhesive-forming material to cause the same to adhere the said covering material to the said core-strand.

2. A method of securing covering material to elastic strands for incorporation into elastic fabrics comprising: first stretching an elastic core-strand; then applying an. adhesive-forming material in strand form and a covering material also in strand form to the elastic core-strand while the same is stretched; and then subjecting the covered strand thus produced to the action of a solvent to effect the softening of the said adhesive-forming material to cause the same to adhere the said covering material to the said core-strand.

3. A method of securing covering material to elastic strands for incorporation into elastic fabrics comprising: first stretching an; elastic core-strand; then applying an adhesive-forming material in strand form and a plurality of oppositely-inclined layers of covering material also in strand form to the elastic core-strand while the same is stretched; and then subjecting the covered strand thus produced to the action of a solvent to eiiect the softening of the said adhesive-forrning material in strand form to cause the same to adhere the said covering material to the said core-strand.

SAMUEL C. LILLEY. 

